Topic: are ipod 3rd and 4th gen backplates interchangable?

I have modified my 4th gen (click wheel, monochrome) 40gb iPod to fit a 32gb CF card, and all is good.

Just wondering though, I have purchased a 3rd gen 10gb iPod (wheel with the 4 seperate buttons above), and the back plate is slightly slimmer. Since the CF card takes up less room than the old 40gb hdd, is is possible to fit the slimmer 3rd gen back on the 4th gen face?